The proposed research focuses on reaction dynamics of biologically interesting molecules in the solid state, which can provide useful models in regard to interactions and dynamics for reactions in membranes and membrane surface. The novel feature of the proposed approach is the use of space and time resolved laser Raman spectroscopy to derive a dynamical concept of reactivity in solid state. As phonons(lattice vibrations) are cooperative motions of solids, a main thrust of the proposal is to investigate the role of phonons in photochemical as well as in thermal rearrangement reactions. Phonon spectra are extensively used to investigate the response when the product chemically perturbs the lattice. In order to investigate any cooperative dynamic distortion of the lattice, the phonon spectra are sampled at spatially resolved sites as a function of time following reaction induction. The role of electron-phonon coupling in photochemical dimerization is investigated by studying phonon side bands in the electronic spectra. The increased understanding of the cooperative changes would have health related implications in areas dealing with actions of antibiotics, drugs and poisons on cell walls. Studies of photochemical reactions should also help in achieving control of light induced mutations, aging and carcinogenesis.